I think for strictly racing, shorter is probably better. The shorter they are, the less flex the bar will have, making your launches more solid. The shorter they are, the beefier the bars need to be as well as you will have less area to flex and absorb the shock when you launch. Mine are 55" from Annin Engineering. Have you checked out Jeff K's ladder bar install write-up? Here: http://www.cumminsforum.com/forum/at...dure_rev1a.pdf
If your gonna be wheel'n/off-roading and you need lots of suspension flex still, then I hear it is best to mount the bar at the center of your wheelbase like they do on the dedicated wheel'n buggy's.
Have you looked at Glacier Diesel's bars? It will be hard to make a set that looks that sharp. :thumbsup
Sold: 1992, D350, Extended Cab, Auto, straight pipe, Banks Power Pack - Purchased in 1992, sold in 1995
Sold: 1995, 4X4, Standard Cab, Auto, striaght pipe, plate, timing - Purchased new in 1995, sold Sep 2003
Sold: 2003, 4X4, QUAD, LWB, Twins, Snow, Helix2, Hot Cp3, Injectors, 315s - 12.32 @ 109mph - Purchased new Sep 2003, sold Jan 2011
92 W250 Ext Cab 5 speed LE, 275k, 3.54's - Purchased slightly used Feb 2011